221012663 has 2 divisors, whose sum is σ = 221012664. Its totient is φ = 221012662.

The previous prime is 221012633. The next prime is 221012689. The reversal of 221012663 is 366210122.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221012663 - 2²² = 216818359 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221012633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110506331 + 110506332.

It is an arithmetic number, because the mean of its divisors is an integer number (110506332).

Almost surely, 2^221012663 is an apocalyptic number.

221012663 is a deficient number, since it is larger than the sum of its proper divisors (1).

221012663 is an equidigital number, since it uses as much as digits as its factorization.

221012663 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 221012663 is about 14866.4946439973. The cubic root of 221012663 is about 604.6059068594.

Adding to 221012663 its reverse (366210122), we get a palindrome (587222785).

The spelling of 221012663 in words is "two hundred twenty-one million, twelve thousand, six hundred sixty-three".